Study On The Preparation Of Magnetic Solid Super Acid And Catalytic Synthesis Of N-butyl Acetate

There is a ability of the solid superacid catalyst to recieve electron doublet and giveprotons in the reaction.Meanwhile,Lewis acid site and Bronsted acid site are predominant init.It is fouced on chemical production such as the catalytic isomerization of alkanes,alkyedesterification,petroleum cracking additive,alkylation of aromatics,aromatics acyl,olefinpolymerization and so on.Many weaknesses of liquid catalyst are overcomed by it,forexample,side reactions serious corrosion equipment,serious environmental pollution,poorthermal stability.However,the catalyst in the reaction includes loss of synergism,small specificsurface,low acid strength.Besides,the problem is also existed that catalyst is too difficult toachieve the rapid separation after reaction.Therefore,this study is applied to the esterificationof the acetic acid and n-butyl alcohol by introducing other oxides and the magnetic solidsuperacid of preparation of magnetic materials multicomponent oxide magneticmaterial.Moreover,the catalytic performance was investigated deeply and optimum operatingconditions and reaction kinetics parameters was achieved to provide theoretical references forindustrialization.With applied magnetic field,it can be completely separated from the reactionsystem after the end of reaction.So it not only solved loss of solid acid synergism,smallspecific surface,low acid strength,but also solved the problem of the rapid separation fromreaction system and catalyst.This paper takes eight water zirconium oxychloride as zirconium source, six wateraluminum chloride as aluminum source, nano nickel ferrite powder for magnetic core, themass fraction of25%of ammonia as the precipitating agent, polyethylene glycol as thedispersant, using nanometer magnetic solid superacid were prepared by the method ofimpregnation precipitation.It is characterized by XRD, FTIR, nitrogen adsorption-desorption,SEM, TEM, VSM, NH3-TPD and other means.The results show that the catalyst is a nano structure, high specific surface area up to313m2/g, the performance of the superparamagneticand super acid characteristics.In order to determine the optimum conditions for: n (acetic acid)=0.2mol, n (acetic acid): n (n-butanol)=1:1.8, the catalyst/acetic acid and n-butanol ratio was0.026g/g, the reaction time is2h, the esterification rate of more than93%,the catalyticproperties are evaluated in the magnetic solid superacid catalysts butyl acetate reaction,researching the mole ratio, catalyst dosage, reaction time, repeated use performance and otheroperating parameters.The recovery of magnetic solid superacid in the external magnetic fieldcan achieve96.8%,And the catalyst is a new friendly green catalysts that can be highlyefficient separated and used repeatly.Through the kinetics of the esterification of acetic acid with n-butanol,the reaction of thepre exponential factor K0is1.37x106(mol-1·L/min), the activation energy of Ea is59.65kJ/mol,ignoring the internal and external diffusion conditions.Magnetic solid superacid to synthesizen-butyl acetate catalyzed is two irreversible reaction.